RAPAPORT... A Tanzanian small-scale miner has recovered a 512-caratdiamond, the largest ever found in the country, according to a Twitter post by a government official.The stone, which sold for $1.4 million, was found earlierthis month by Joseph Temba in the Shinyanga region, Kitila Mkumbo, permanent secretary at Tanzania's Ministry of Water, wrote on the social-media site last week. Temba sold the stone through the Ministry of Minerals, andcalled on other small-scale miners to follow suit, according to the BBC. Tanzania's main exports include gold, copper, platinum anddiamonds. The Williamson diamond mine, owned by Petra Diamonds, is thecountry's largest source of rough stones. Image: The 512-carat diamond. (Kitila Mkumbo/Twitter)